Being single is amazing. I know it doesn't suit everyone, but it honestly is wonderful.
Your time is your time to do whatever you like (obviously taking children into account).
No worry of them having an affair, any sort of abuse, gaslighting or manipulation.
Be who YOU want to be. You don't need to be 'on' or try to impress anyone else. You don't need to answer to anybody.
As people have said, the freedom is amazing. You are in total control of everything.
You don't have to come home to someone in a bad mood, you don't have to base what you cook/watch etc. Around someone else.
Obviously it's different if you don't live with your partner, but some of these things still do apply.
No disturbed sleep which is very important.
So many reasons, could go on all day.
I have 2 newlywed friends (married less than 6 months) who complain to me about their grumpy husbands and having to put up with their moods. Another friend who got married and now is divorced because of her husband's affair.
I just wish that more people I knew took the decision to be single. However I understand that it's human nature to want somebody.
When men ask "How are you still single ?!" or people say "And that's why I'm still single at X age." They don't believe that people can be choose to be single and happy.
Single should be celebrated, whatever age you are. I know it's probably easier for me though as I don't want to have children, whereas I have single friends in their mid-30s who feel time is running out. I would like to be a foster carer later down the line.
I am going to continue being single and happy, and show people that it doesn't mean there is anything wrong with you or that you are not loveable.